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Topic: electronic instrumentation recalibration (Read 5316 times) previous topic - next topic

electronic instrumentation recalibration

Reply #15
Quote from: 20thanvcat;460926
the cluster was swapped due to speedo light out (no numbers and printed circuit board separating ) running stock size tires (as per door sticker) 3.73 8.8 from 88 tc (disk)
I also noted tach is off (a lot) and i saw a thread about installing a resistor? but can't find it now (everyone saying there not accurate anyhow ) and want it somewhat close.

For digital tach I dunno, has to be two versions as that cluster was used with 6&8 cyl... Scott mentions a mod, you'll have to pursue that avenue...

If you can't find a issue with cluster skewing speed, installing 23T gear should reduce error to approx 6-7% vs 13%...

electronic instrumentation recalibration

Reply #16
i have copper "tape" i was going to try to repair old one - nothing to loose

electronic instrumentation recalibration

Reply #17
Quote from: 20thanvcat;460947
i have copper "tape" i was going to try to repair old one - nothing to loose

Waste of time... If you don't make solid connections such as Scott suggested by soldering, it probably won't work and if it did there is zero chance it will last...

electronic instrumentation recalibration

Reply #18
Quote from: 20thanvcat;460947
i have copper "tape" i was going to try to repair old one - nothing to loose


if you have spare network cable or any device that is trash that has tiny wire use that.

example,, sometimes you run across old power supplies from a PC where there is a flat ribbon cable jumper of some sorts.

if i recall correctly,, and i can confirm by older pics of min,, there are about 7 runs of flex print dumping into the bottom of the speedo.

you skin/tin/flux & solder and alcohol clean then seal.

At the time i did not find any ribbon cable lying around in my bins,, and used donor material from an old network cable to obtain the "flex" 28awg jumpers which i grafted in and they are about 2'' long each.

my goal was to insure that the complete bend experienced by the flex print was now "just jumper wires".

use a magnefying glass during your work tasks,, the separation between the runs is like tighter than 1/32''

electronic instrumentation recalibration

Reply #19
Buy a speedo recalibrate  thingy. They are expensive but would fix the problem.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

electronic instrumentation recalibration

Reply #20
My stock, never been changed digital tachometer, is off by quite a bit: http://www.foxtbirdcougarforums.com/showthread.php?38600-The-stock-digital-tach-is-apparently-very-inaccurate&highlight=Digital+tachometer
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

electronic instrumentation recalibration

Reply #21
[COLOR="#FF0000"]running stock size tires (as per door sticker)[/COLOR]

What does that mean?  Can you just post up the rear tire size as read off the tire?  If we assume you have a 225/60/16 then the 7/21 setup sounds about right for 3.73's but if your rear tires are not that size then we are just a bunch of monkeys at the zoo flinging poo at the visitors.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

electronic instrumentation recalibration

Reply #22
225/60/15 is stock for 87 20th anniversary , all of the mods are normal "mustang" mods early 90s t5, 3.73 gears 225/60/15 tires on stock rims

electronic instrumentation recalibration

Reply #23
And you are 100% sure the drive gear on the output shaft of the T5 is a 7 tooth?

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

electronic instrumentation recalibration

Reply #24
its yellow so it should be

electronic instrumentation recalibration

Reply #25
So get the black one?

6 tooth driven gear for gears higher then 3.73
https://lmr.com/item/LRS-17285A/79-98-Mustang-6-Tooth-Speedo-Drive-Gear
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

electronic instrumentation recalibration

Reply #26
Okay, there is an 8 tooth drive gear that is a translucent yellow greenish color. This was standard in the Mustang T-5's starting in 1990. If you look at the drive gear on the output shaft through the speedo adapter hole with a flash light the 8 tooth gear will look yellow.

If this is a stock 90-93 T-5 then you have an 8 tooth drive gear. I would highly suggest you go to a black six tooth gear. The only way to verify is to pull the tail housing cover.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

electronic instrumentation recalibration

Reply #27
Wanna hear about shaged?  I've got a full 4R70W stack in my AOD (AOD output shaft - 7 tooth, 4R70W - 8 tooth). The drive gear is machined into the output shaft.  That means that when I had a 3.27:1 I could run a purple driven gear (21 tooth), and be straight; but now I have a 3.73:1, and there is no driven gear to correct my speedo.  At all times, my speedo reads 5 to 7 MPH high depending on my speed.  I have to get a FRPP calibration box to go in-line with my OSS to correct my speed.  OR, I can build an aftermarket cluster, or buy a dakota digital VHX.  4R70W's are fully electronic normally, so to correct speedo is usually a matter of hooking up IDS and making a couple careful edits.  Not the case for me.

electronic instrumentation recalibration

Reply #28
The trans was just apart to put 3rd synchro (output shaft) so I'm sure it's yellow, so the easier fix is 23 teeth driven gear, ordered one last night should be here Monday/Tuesday. the real question was if there is a different sensor for the electronic dash, since every other sensor is different i:e temp, oil pressure, and fuel. 
Because everything else seems to be in line with what Ford suggests (A T5 with a yellow 7 tooth gear should run a red 21 tooth gear if you have 3.73 gears, and 255/60/15 tires)

electronic instrumentation recalibration

Reply #29
Quote from: TheFoeYouKnow;460979
Wanna hear about shaged?  I've got a full 4R70W stack in my AOD (AOD output shaft - 7 tooth, 4R70W - 8 tooth). The drive gear is machined into the output shaft.  That means that when I had a 3.27:1 I could run a purple driven gear (21 tooth), and be straight; but now I have a 3.73:1, and there is no driven gear to correct my speedo.  At all times, my speedo reads 5 to 7 MPH high depending on my speed.  I have to get a FRPP calibration box to go in-line with my OSS to correct my speed.  OR, I can build an aftermarket cluster, or buy a dakota digital VHX.  4R70W's are fully electronic normally, so to correct speedo is usually a matter of hooking up IDS and making a couple careful edits.  Not the case for me.

Most AOD also have the eight tooth output shaft... Generally only stuff like Super Coupe & pickups/vans had the seven tooth...